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TuningBot DTC Database · v4.37.14

U063C Lost Communication With Coolant Bypass Valve Actuator B

Generic (OBD-II) interpretation in the TuningBot DTC database.

U · NetworkNetworkOBD2

What U063C means

U063C
Lost Communication With Coolant Bypass Valve Actuator B Generic · network Data confidence 65%

The control module stopped receiving expected network messages from the Coolant Bypass Valve Actuator B node on the vehicle communication bus.

Symptoms

  • Multiple warning lamps possible
  • Functions of the affected module unavailable

Possible causes

  • CAN bus wiring fault (open, short, chafed harness)
  • Faulty control module loading the bus
  • Connector or terminal corrosion
  • Power supply or ground fault of a module

Recommended checks

  • Perform a full-module scan to map which modules communicate
  • Check CAN bus resistance and voltages at the diagnostic connector
  • Inspect wiring and connectors of the affected module
  • Check module power supply and grounds
  • Disconnect suspect modules one at a time only with a documented procedure

Related and nearby codes

How to read U063C

U

Network: communication between control units.

0

Generic SAE-standard code: same meaning on every make.

63C

Specific fault index within the subsystem.

Frequently asked questions about U063C

What does U063C mean?

Lost Communication With Coolant Bypass Valve Actuator B. The control module stopped receiving expected network messages from the Coolant Bypass Valve Actuator B node on the vehicle communication bus.

Is U063C generic or manufacturer-specific?

U063C is a generic OBD-II code: it has the same meaning on every make and model that follows the SAE standard.

Can TuningBot remove U063C at file level?

Not guaranteed. Powertrain (P) codes can be reliably disabled in the ECU calibration, but body, chassis and network codes depend on the specific control unit and how the fault is implemented - some can be handled, some cannot. Ask for a quote and our engineers will check your file and tell you, free of charge, whether U063C is removable in your case.

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